<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="js/vue.js"></script>
</head>
<body>
    <div id="app">
        <div>
            <span>名：</span>
            <span>
                <input type="text" v-model="firstName">
            </span>
        </div>
        <div>
            <span>姓：</span>
            <span>
                <input type="text" v-model="lastName">
            </span>
        </div>
        <div>{{fullName}}</div>
    </div>
    <script>
        /*
            侦听器 watch
        */
        var vm = new Vue({
            el:'#app',
            data:{
                firstName:'jim',
                lastName:'Green',
                // fullName:'jim Greens'
            },
            computed: {
                fullName:function(){
                    return this.firstName + ' ' + this.lastName;
                }
            },
            // watch: {
            //     firstName:function(val){
            //         this.fullName = val +'  '+this.lastName;
            //     },
            //     lastName:function(val){
            //         this.fullName = this.firstName + '  '+val;
            //     }
            // },
            methods:{
                
            }
        })
    </script>
</body>
</html>